Passive separation

[Glassyfo]

I think I once saw a post where liquids were separated based on what level they floated, and I'm wondering if something like that can be used for gasses?

[Caochu]

You are talking, I guess, of the various densities that cause the separation of gasses and liquids. The game reflects that, as you observed about liquids, and does the same with the gasses. I redirect you to this topic, that shows in its second post the natural rearrangement of gasses :

However, It seems to me that oxygen and polluted oxygen now don't separate themselves anymore, or at least at a very slow rate I never actually observed during my gameplay.

 

Edit : oh, by browsing deeper the topic I show above, I found the one topic about liquids you may be referring to :

So now I understand that you were asking for a whole system like that. Saturnus showed in the ninth post of the link above a thing that could help you separate and sort gasses, but not as free energy as for the liquid separation.

[crypticorb]

Absolutely, and this is a core concept of the Self-Powering Oxygen Modules. Simply put, with an electrolyzer you can have 2 gas pumps for the oxygen and one for the hydrogen, and position them so that the highest pump will always be immersed in hydrogen, and the lower pumps always get oxygen, due to the natural separation of the gasses.

This is my latest and most efficient SPOM that uses this concept, zero filters needed:

The entire build can be made from cheap and easily obtained materials. The electrolyzer makes hydrogen, which always goes up to the hydrogen pump, and the oxygen floats down to the oxygen pumps. The hydrogen is pumped away to fuel two hydrogen generators that power the whole thing, and the oxygen is pumped to supply my base and 16 exosuits.

[Glassyfo]

I just wanted to sort hydrogen, oxygen, chlorine and natural gas without using mechanical filters.

[Soulwind]

Separation of gas using pipe element filters and cutoff valves is easy and just requires some refined metal and 5W power per gas type to be separated.

Mechanical separation of H2 and O2 from an electrolyzer is also easy. 

Purely mechanical separation of other mixtures of gas can be done but is a bit more complicated.

Liquid separation is easy but needs a bit of room to accomplish without power.

[Saturnus]

1 hour ago, bleeter6 said:

I just wanted to sort hydrogen, oxygen, chlorine and natural gas without using mechanical filters.

How about automation filters?

You could build a system like this. It filters into 4 separate lines and includes an output line block sensor to skip filtering if output line is blocked. The gas will then just be recirculated until it completely stop the filtering of all gases eventually. Gas storages only used for testing purposes. It uses no power at all. Don't be fooled by the shut off valve saying they require power. They don't, they just need to be connected to a power source.

Here's an exploded view of each filter section so the principle is clearer.

[crypticorb]

1 hour ago, bleeter6 said:

I just wanted to sort hydrogen, oxygen, chlorine and natural gas without using mechanical filters.

Mechanical filters typically implies using natural separation of gasses and airflow tiles, or the clever use of valves to sort gasses. Such systems typically don't use power, and aim to be as reliable as possible. Standard filters (the ones unlocked by filtration research) take 120W of power, but are 100% effective.

So far as I know, it is nearly impossible to separate multiple gasses with airflow tiles and passive separation, because when 3 gasses mix you can only reliably separate the highest from the lowest. Electrolyzers are easy because it's always only hydrogen/oxygen in a perfectly contained system. Separating out CO2, oxygen, chlorine, and hydrogen from each other in the bottom of a base is difficult without active filters, because the vertical height each gas settles isn't guaranteed.

The best of both worlds is Automation Filters. @Saturnus above posted a good example, but it's more for experienced players. Here's an even more boiled down version. Using a gas pipe element sensor and a pipe shutoff, it has a 100% filter with incredibly low power usage.

The key thing to note is that you MUST ensure that the filtered element outgoing pipe is not blocked/backfilled, or the setup will let packets of the desired gas slip through unfiltered. Saturnus's setup ensures flow even if the pipe is blocked, but is more complex.

You can ensure the pipe never gets blocked by using a gas reservoir, or burning the gas off in a hydrogen generator, CO2 skimmer, or pumping it out of the base.

[Glassyfo]

3 minutes ago, crypticorb said:

Mechanical filters typically implies using natural separation of gasses and airflow tiles, or the clever use of valves to sort gasses. Such systems typically don't use power, and aim to be as reliable as possible. Standard filters (the ones unlocked by filtration research) take 120W of power, but are 100% effective.

So far as I know, it is nearly impossible to separate multiple gasses with airflow tiles and passive separation, because when 3 gasses mix you can only reliably separate the highest from the lowest. Electrolyzers are easy because it's always only hydrogen/oxygen in a perfectly contained system. Separating out CO2, oxygen, chlorine, and hydrogen from each other in the bottom of a base is difficult without active filters, because the vertical height each gas settles isn't guaranteed.

The best of both worlds is Automation Filters. @Saturnus above posted a good example, but it's more for experienced players. Here's an even more boiled down version. Using a gas pipe element sensor and a pipe shutoff, it has a 100% filter with incredibly low power usage.

The key thing to note is that you MUST ensure that the filtered element outgoing pipe is not blocked/backfilled, or the setup will let packets of the desired gas slip through unfiltered. Saturnus's setup ensures flow even if the pipe is blocked, but is more complex.

You can ensure the pipe never gets blocked by using a gas reservoir, or burning the gas off in a hydrogen generator, CO2 skimmer, or pumping it out of the base.

So it can't be done. That's okay, this was largely a curiosity on my part anyway. I already know and use the suggestions offered thanks.

[Zarquan]

On 10/11/2018 at 8:25 AM, bleeter6 said:

So it can't be done. That's okay, this was largely a curiosity on my part anyway. I already know and use the suggestions offered thanks.

You can separate any three gases by the level they float at using effectively CO2 locks and H2 locks.  I use this to filter CO2 out of my base.  The only problem is that it is slow, as gases move a lot slower than liquids.  I will create a build showing this later.  It can be used on any gas except separating O2 from polluted O2, as they float at the same level.